Metropolitan areas on this map are ranked from most congested to least congested, based on their projected Travel Time Indices (TTI) in 2030.

TTI is defined as the ratio of travel time in peak hours to the travel time in off-peak hours. For instance, an index of 1.5 means that travel time in the peak hour is 50 percent longer than in the off-peak.

For more information about a city, click its numbered marker on the map, or click on the list on the right of this page.
Use controls in the upper left of map to pan and zoom.